Humanity survives Kama Sutra apocalypse

Security watchers say the Kama Sutra worm, which is programmed to overwrite files on infected Windows PCs today, will have a damaging but not catastrophic effect.

The Kama Sutra worm (AKA Nyxem-E or Blackworm) poses as an email message offering a variety of salacious content. Subject lines used in the malicious emails include: The Best Videoclip Ever, Fw: SeX.mpg, Miss Lebanon 2006 and Fuckin Kama Sutra pics. The worm, which can also spread across network shares, only affects Windows PCs.

Windows users who fall for this ruse wind up with an infected machine and disabled security software. Once infected, machines start to spew out additional copies of the worm. Worse still, Nyxem-E is also programmed to overwrite files on Friday February 3, and the third day of every month thereafter. The worm overwrites DOC, XLS, MDB, MDE, PPT, PPS, ZIP, RAR, PDF, PSD and DMP files on local drives.

Email security firm MessageLabs has stopped four million copies of the "PC thrashing" worm from 200,000 different IP addresses since its first appearance on January 16. An estimated 600,000 PCs worldwide were infected at some point, with the US, India and Peru reckoned to harbour the greatest number of compromised machines.

However, many users of infected machines have cleaned up their act, according to Messagelabs. It estimates the worm is currently live on 20,000 IP addresses, suggesting 20,000 individual home users or organisations worldwide are currently infected by Kama Sutra, a big fall from earlier this week. MessageLabs has seen worm 'clean-up' from approximately 11,000 IP addresses a day.

"This virus was created purely for malicious intent, unlike the majority of viruses we see today that are instead looking for backdoors into people's machines to send spam or steal data. We are hopeful that this does not indicate a return to destructive, nuisance viruses. However, this virus writer did do one good thing, intentionally or not, he or she provided a two week window before activation of the payload to destroy data. This has allowed many smart computer users and businesses an opportunity to disinfect their machines and hopefully take protective measures" MessageLabs senior virus technologist Alex Shipp said.

Anti-virus firm McAfee also says Kama Sutra will have a minimal impact on computer users. It estimates a maximum of 15,000 machines in the US are infected.

The Nyxem virus family that spawned Kama Sutra (AKA Nyxem-E) made its debut in March 2004. The first worm in the series launched a DDoS attack against the "New York Mercantile Exchange" website (www.nymex.com). The motive and perpetrator of the virus series remains unknown. ®